momentary communication problems and to act on these if they are excessive. • StatusReadFaultCounter: Used to tolerate momentary communication problems and to act on these if they are excessive.
•AbnormalFaultCounter: Used to tolerate momentary abnormality
•StagingOrder: Used to record the
•Storage for each item described in the Periodic data polling section • Storage for each item described in the Slave status read response section • Slave Command - the command word from the master to the slave.
Features common to all states
•Whenever a slave Sola device is not in an expected condition then a recovery function is used to set up timers to give a faulty slave: — minimum time that it must appear to be OK, and
— limit how long a slave has to recover from any error.
•If the slave status read was bad then the slave's FaultCounter is incremented and if it to reaches the fault value tries, then a recovery action is invoked. This action does nothing else if the status read was Bad. If the slave status read was OK then the status function puts the slave read response data in a slave status table. If a transition to another state is indicated then the SlaveState is simply set to the indicated state.
Data poll response handling
Valid Response Message
When a slave Sola responds with a properly formatted message it is examined to see if Slave enable value is "Enable for Sola Master".
•If the "Enable for Sola Master" value is not present then the slave status table is checked and if the slave is not in the table then the message is ignored (this is normal). However if the slave is in the table then the message is stored as usual and the slave will invoke the action as a disabled slave and cause recovery action to occur.
•If the "Enable for Sola Master" value is present then the slave status table is checked and if the slave is not in the table then the slave data is stored in an empty position in the table. However if the slave is in the table then the message is stored as usual (this is the normal case).
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Date: 8-4-2010
Revision: 0
Form: 2396
INVALID RESPONSE OR NO RESPONSE
When a Sola responds to a data poll with an improperly formatted message or it does not respond then the slave status table is checked and: If the polled slave device is in the table then the Data Poll Fault is noted. If this causes a fault counter to exceed the fault value then the SetRecovering handling is invoked.
SlaveState states
Recovering A slave that is recovering is checked once per second. If the slave has recovered the SlaveState table is changed to Available. If the slave has not yet recovered when its recovery timer reaches the RecoveryTimeLimit then: If the slave is not enabled for the Sola LL master its SlaveState table is Set to Unknown (which logically removes it from the slave table). Otherwise the Recovery- LimitTimer is cleared which starts a new recovery measurement and the slave remains in recovery (indefinitely).
Available A slave in the Available state remains that way until the Stager moves it into the AddStage state or the ProcessSlaveStatus action moves it to some other state.
AddStage A slave in the AddStage state remains that way until the ProcessSlaveStatus moves it to Firing or some other state, or the Stager times out and moves it into the Recovering state if it fails to fire.
SuspendStage A slave in the SuspendStage state remains that way until the ProcessSlaveStatus moves it to some other state, or the Stager times out and moves it into either the Firing or the Available state.
Firing A slave in the Firing state remains that way until the ProcessSlaveStatus moves it to some other state, or the Stager drops the stage and moves it into the Available state.
OnLeave A slave in the OnLeave state remains that way until the ProcessSlaveStatus moves it to some other state.
Disabled A slave in the Disabled state remains that way until the ProcessSlaveStatus moves it to Recovering.
Demand and Priority
Different sources of demand can cause the LL master to operate in different ways. These sources have a priority relationship.
CH Demand